Number of trials until success for successful participants

[Guest]

I have the following problem:
Given a Bernoulli trial with probability of success p and a number of trials x, what is the expected number of trials until success in a case success was achieved in x trials?

e.g. if p = 0.02 and x = 60, I would like to find the expected number of trials taken in case of succes within 60 trials. I understand it is lower than 1/0.02 and will decrease with x but don't know how to proceed.

I think it's simple and I'm missing something basic, anyway thanks ahead !